TY - JOUR
T1 - ALMA CO observations of a giant molecular cloud in M 33
T2 - Evidence for high-mass star formation triggered by cloud–cloud collisions
AU - Sano, Hidetoshi
AU - Tsuge, Kisetsu
AU - Tokuda, Kazuki
AU - Muraoka, Kazuyuki
AU - Tachihara, Kengo
AU - Yamane, Yumiko
AU - Kohno, Mikito
AU - Fujita, Shinji
AU - Enokiya, Rei
AU - Rowell, Gavin
AU - Maxted, Nigel
AU - Filipović, Miroslav D.
AU - Knies, Jonathan
AU - Sasaki, Manami
AU - Onishi, Toshikazu
AU - Plucinsky, Paul P.
AU - Fukui, Yasuo
N1 - Funding Information:
This paper makes use of the following ALMA data: ADS/JAO ALMA#2018.1.00378.S. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada), NSC and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. Based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESA), and the Canadian Astronomy Data Centre (CADC/NRC/CSA). This study was financially supported by Grants-in-Aid for Scientific Research (KAKENHI) of the Japanese Society for the Promotion of Science (JSPS, grant nos. 16K17664, 18J01417, and 19K14758). K. Tokuda was supported by NAOJ ALMA Scientific Research Grant Number 2016-03B. H.S. was also supported by the ALMA Japan Research Grant of NAOJ Chile Observatory (grant no. NAOJ-ALMA-226). M.S. acknowledges support by the Deutsche Forschungsgemeinschaft through the Heisenberg professor grants SA 2131/5-1 and 12-1. We are also grateful to the anonymous referee for useful comments which helped the authors to improve the paper.
Publisher Copyright:
© The Author(s) 2020. Published by Oxford University Press on behalf of the Astronomical Society of Japan. All rights reserved.
PY - 2021/1/1
Y1 - 2021/1/1
N2 - We report the first evidence for high-mass star formation triggered by collisions of molecular clouds in M 33. Using the Atacama Large Millimeter/submillimeter Array, we spatially resolved filamentary structures of giant molecular cloud 37 in M 33 using 12CO(J = 2–1), 13CO(J = 2–1), and C18O(J = 2–1) line emission at a spatial resolution of ∼2 pc. There are two individual molecular clouds with a systematic velocity difference of ∼6 km s-1. Three continuum sources representing up to ∼10 high-mass stars with spectral types of B0V–O7.5V are embedded within the densest parts of molecular clouds bright in the C18O(J = 2–1) line emission. The two molecular clouds show a complementary spatial distribution with a spatial displacement of ∼6.2 pc, and show a V-shaped structure in the position–velocity diagram. These observational features traced by CO and its isotopes are consistent with those in high-mass star-forming regions created by cloud–cloud collisions in the Galactic and Magellanic Cloud H II regions. Our new finding in M 33 indicates that cloud–cloud collision is a promising process for triggering high-mass star formation in the Local Group.
AB - We report the first evidence for high-mass star formation triggered by collisions of molecular clouds in M 33. Using the Atacama Large Millimeter/submillimeter Array, we spatially resolved filamentary structures of giant molecular cloud 37 in M 33 using 12CO(J = 2–1), 13CO(J = 2–1), and C18O(J = 2–1) line emission at a spatial resolution of ∼2 pc. There are two individual molecular clouds with a systematic velocity difference of ∼6 km s-1. Three continuum sources representing up to ∼10 high-mass stars with spectral types of B0V–O7.5V are embedded within the densest parts of molecular clouds bright in the C18O(J = 2–1) line emission. The two molecular clouds show a complementary spatial distribution with a spatial displacement of ∼6.2 pc, and show a V-shaped structure in the position–velocity diagram. These observational features traced by CO and its isotopes are consistent with those in high-mass star-forming regions created by cloud–cloud collisions in the Galactic and Magellanic Cloud H II regions. Our new finding in M 33 indicates that cloud–cloud collision is a promising process for triggering high-mass star formation in the Local Group.
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U2 - 10.1093/pasj/psaa045
DO - 10.1093/pasj/psaa045
M3 - Article
AN - SCOPUS:85117329082
VL - 73
SP - S62-S74
JO - Publication of the Astronomical Society of Japan
JF - Publication of the Astronomical Society of Japan
SN - 0004-6264
ER -